| A | B |
|---|
| soil | the loose , weathered material on Earth's surface in which plants can grow |
| bedrock | the solid layer of rock beneath the soil |
| soil | is a mixture of rock particles, minerals, decayed organic matter , water and air |
| humus | is a dark-colored substance that forms as plant and animal remains decay |
| fertility | a measure of how well the soil supports plant growth |
| loam | soil that is made up of equal parts of clay, sand, and silt |
| soil horizon | is a layer of soil that differs in color and texture from the layers above or below it |
| topsoil | a crumbly , dark brown soil that is a mixture of humus, clay and other materials |
| subsoil | a type of soil that usually consists of clay and other particles washed down from the topsoil |
| topsoil | A horizon |
| subsoil | B horizon |
| litter | a loose layer formed by the leaves of plants that shed |
| decomposer | organisms that break the remains of dead organisms into smaller pieces and digest them with chemicals |
